In manufacturing a semiconductor device, a processing for removing a partial region of a processing target object may be performed. For example, a method for removing a silicon oxide film from a processing target object is disclosed in Japanese National Phase Patent Laid-Open Publication No. 2007-515074.
In the method disclosed in Japanese National Phase Patent Laid-Open Publication No. 2007-515074, HF and NH3 react with silicon oxide in a chemical processing chamber to generate (NH4)2SiF6. That is, a surface of the silicon oxide film is altered by the reaction. Subsequently, the processing target object is carried into a thermal processing chamber different from the chemical processing chamber, and the processing target object is heated in the chemical processing chamber so as to thermally decompose the (NH4)2SiF6 in the altered layer. In the processing disclosed in Japanese Patent Laid-Open Publication No. 2007-515074, the silicon oxide film is selectively removed by the alteration and thermal decomposition. Further, Japanese National Phase Patent Laid-Open Publication No. 2013-503482 discloses a process of altering a carbon-containing film by plasma of a gas containing NH3 and NF3, and removing the altered layer by the thermal decomposition.